import torch
x = torch.tensor([1,2,3,4,5])
x = torch.as_tensor(x,dtype=torch.float32)
print("x:",x)
saved_mean = x.mean(dim=0, keepdim=True)
print("saved_mean:",saved_mean)
saved_var = x.var(dim=0, 
                      keepdim=True,
                      unbiased=True # unbiased无偏估计。
                      )
print("saved_var:",saved_var))
